Pilot using abnormal loudness growth contours to fit hearing aids
Research type
Research Study
Full title
A pilot study using individual patient loudness growth data to fit hearing aid compression levels in new adult users.
IRAS ID
211564
Contact name
Helen Pryce
Contact email
Sponsor organisation
University of Aston
Duration of Study in the UK
0 years, 4 months, 31 days
Research summary
Abnormal loudness growth of sounds and reduced dynamic range is characteristic of sensorineural hearing loss. Current hearing aid fitting strategies attempt to account for diminished dynamic range by using gain compression. Compression amplifies quiet sounds more to make them audible and loud sounds less so that they do not become uncomfortable - compressing the sound signal into an individual’s reduced audible range. However, these methods do not directly take into account an individual’s subjective perceptual loudness growth curves. The present pilot study will investigate the feasibility of measuring the loudness contour growth data of an individual's dynamic hearing range at each frequency, and whether this can be used when programming their hearing aids compression settings to improve speech intelligibility in noise and minimise uncomfortable loudness when compared to standard clinical practice of prescribing gain compression values using NAL-NL2 prescription formula alone. Speech intelligibility is the primary goal of hearing aid intervention and uncomfortable loudness is one of the main negative impacts of current hearing aids (Johnson, Cox & Alexander, 2010), thus investigating ways to improve both is of clinical importance for maximising patient benefit from hearing aids. Patient subjective loudness growth will be measured using Cox’s loudness contour test (Cox etal., 1997), a validated test for this measure. The intervention impact will be measured by comparing the adapted fitting strategy to standard clinical practice by way of the Bamford-Kowel-Bench speech in noise test (Wilson, McArdle and Smith, 2007), and the abbreviated profile of hearing aid benefit questionnaire (Cox & Alexander, 1995). This study will gather initial pilot data including data on patient recruitment, retention and trial compliance. The above mentioned tools will be used to measure abnormal loudness growth curves, calculate individual compression settings and measure their impact on speech intelligibility and uncomfortable loudness will also be assessed for their suitability.
REC name
London - Surrey Research Ethics Committee
REC reference
16/LO/1787
Date of REC Opinion
18 Oct 2016
REC opinion
Favourable Opinion